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Let \(X\)  and \(Y\)  be arbitrary sets and \(c:X\times Y\mapsto (-\infty ,\infty )\)  be a function. A subset \(\Gamma \subset X\times Y\)  is said to be \(c\) -cyclically monotone, or \(c\) -CM, if for any \(N\in \mathbb {N}\) , permutation \(\sigma \) , and family of points \((x_1,y_1),\ldots ,(x_n,y_n)\)  in \(\Gamma \) , we have
\(\sum _{i=1}^{N}c(x_i,y_i)\le \sum _{i=1}^N c(x_i,y_{\sigma (i)}).\) 
